In chest radiography, which statement about grids and air gap is most accurate?

• A. Grids increase scatter and decrease dose.
• B. Air gap increases scatter and preserves sharpness.
• C. Grids reduce scatter while increasing dose; air gap reduces scatter with potential loss of sharpness; the choice depends on patient size and clinical objective.
• D. Air gap reduces both scatter and sharpness equally.

Answer: (C)